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The Relationship Between Strong Earthquake Activity of M_S≥7.0 on the Chinese Mainland and the West Kunlun-A'nyêmaqên Secondary Arcuate Tectonic Zone
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作者 ZhangXiaodon WangHuimin LuMeimei YuSurong 《Earthquake Research in China》 2004年第2期171-177,共7页
The active and quiet phenomenon of moderate strong earthquakes one year before the earthquakes with M S≥7.0, the spatial distribution characteristics of the solid tide modulating and triggering earthquakes and the st... The active and quiet phenomenon of moderate strong earthquakes one year before the earthquakes with M S≥7.0, the spatial distribution characteristics of the solid tide modulating and triggering earthquakes and the strong earthquake mechanisms on the Chinese continent have been studied. The secondary arcuate tectonic zone composed of the west Kunlun-Anyêmaqên faults is believed to be a very important boundary to characterize strong earthquake activity of M S≥7.0 on the Chinese continent, that is, a boundary between the seismically active region and the quiet region of moderately strong earthquakes one year before earthquakes with M S≥7.0, and a boundary of the spatial distributions between the solid tide modulating strong earthquakes (M S≥7.0) and the non-modulating ones. It might be related with the characteristics of spatial distribution of focal mechanism solutions of strong earthquakes on the Chinese Continent. 展开更多
关键词 Arcuate tectonic zone Boundary zone Strong earthquake Seismicity characteristics
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《史记》词语古今释义考正
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作者 管锡华 《四川师范大学学报(社会科学版)》 北大核心 2002年第1期84-89,共6页
对《史记》中“午”、“景”等 1 5个词语的古今释义作了研考 ,纠正了古今释义的错误和偏颇 ,亦对《史记》
关键词 词语 释义 《史记》 '' '' '' '' '烈' '' '' ''
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Male Allocare in Rhinopithecus bieti at Xiaochangdu, Tibet: Is It Related to Energetic Stress? 被引量:2
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作者 向左甫 霍晟 肖文 《Zoological Research》 CAS CSCD 北大核心 2010年第2期189-197,共9页
Male allocare among nonhuman primates has frequently been investigated from the perspective of the caretaker. Here we examined whether male allocare relates to environmental factors or the females' energetic stress. ... Male allocare among nonhuman primates has frequently been investigated from the perspective of the caretaker. Here we examined whether male allocare relates to environmental factors or the females' energetic stress. We researched the possible differences of allocare between sexes in free-ranging black-and-white snub-nosed monkeys (Rhinopithecus bieti) in Tibet. A combination of stepwise least squares regression analysis was used to identify the influence of ecological factors (temperature, rainfall, etc.) and infant age that best account for seasonal variation of allocare. The results indicate, except for the functions of infant age, however, that male allocare is a negative function of temperature and female allocare is a positive function of temperature. Specifically, we tested the energetic stress hypothesis, which predicts that the energetic burden of females in a severe environment favour an increased rate of male allocare during the seasons of high energetic stress. We analyzed the allocare difference between high energetic stress season (Mar - Apr), when temperature was low, food availability was scarce, and infants were young, and low energetic stress season (Jun - Aug), based on data obtained during June 2003 - June 2004. Our results supported the energetic stress hypothesis because male allocare in high energetic stress season was higher than that of in low energetic stress season and female allocate was reverse. Therefore, we propose it is the energetic stress on female that make male allocare possible. Male take these interests for other aims and meet some functional hypothesis, which are addressed from the perspective of the male. 展开更多
关键词 Parental investment Intensive male infant caretaking Energetic stress hypothesis COLOBINAE
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Viscoplastic friction and microstructural evolution behavior of laser-clad Co-Cr-Ni-Mo coating 被引量:2
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作者 李瑞迪 李京龙 +2 位作者 梁毅 籍成宗 袁铁锤 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第3期681-691,共11页
The viscoplastic friction and nanostructure formation mechanism of laser-clad Co-based coating were studied by rotary friction between laser-clad Co-Cr-Ni-Mo coating and WC-Co rod.The friction coefficient,friction int... The viscoplastic friction and nanostructure formation mechanism of laser-clad Co-based coating were studied by rotary friction between laser-clad Co-Cr-Ni-Mo coating and WC-Co rod.The friction coefficient,friction interface temperature and axial displacement—time curves during rotary friction process were measured.The results showed that all the curves firstly experienced rising stage and then steady stage.The rising stage corresponded to sliding friction while the steady stage corresponded to viscoplastic friction.After viscoplastic friction processing,three typical zones of viscoplastic deformation zone,thermo-mechanically affected zone,and original laser-clad zone can be observed successively from the friction surface to the interior.The viscoplastic deformation significantly crushed the network M23C7 phase in original laser-clad zone and made it dispersively distributed with equiaxial shape and in nano-scale.The viscoplastic zone,in width of 37-131 μm,is mainly characterized by refined M23C7 and α-Co phase with grain size bellow 50 nm,and even a small quantity of amorphous.Thus,the hardness of viscoplastic zone about HV997 was improved compared with the hardness of original laser-clad zone about HV600. 展开更多
关键词 viscoplastic deformation severe plastic deformation laser cladding Co-Cr-Ni-Mo coating nanostructure rotary friction
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Effect of processing route on grain refinement in pure copper processed by equal channel angular extrusion 被引量:2
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作者 唐超兰 李豪 李赛毅 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第7期1736-1744,共9页
An experimental study of the microstructures in pure copper billets processed by 8 passes of equal channel angular extrusion (ECAE) via an extended range of processing routes with a 90° die is carried out. Each... An experimental study of the microstructures in pure copper billets processed by 8 passes of equal channel angular extrusion (ECAE) via an extended range of processing routes with a 90° die is carried out. Each processing route is defined according to the inter-pass billet rotation angle (χ), which varies from 0° to 180°. According to the generation of high-angle boundaries and reduction of grain size by electron backscatter diffraction (EBSD) measurements, the grain refinement is found to be most efficient for route with χ=90°and least efficient with χ=180°, among the seven routes studied. This trend is supported by supplementary transmission electron microscopy (TEM) measurements. Comparison of the EBSD and TEM data reveals the importance of considering the non-equiaxity of grain structures in quantitative assessment of microstructural differences in ECAE-processed materials. 展开更多
关键词 pure copper equal channel angular extrusion severe plastic deformation strain path grain refinement
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是酋邦,还是国家?——再论金朝初年女真政权的国家形态 被引量:5
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作者 程妮娜 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2020年第4期72-85,共14页
关于金朝太祖、太宗时期政治、社会制度是国家形态,还是前国家形态——酋邦(军事部落联盟、部族制),学界有两种截然不同看法。学界相关研究中使用最为频繁的史料存在着解读失误和运用不当的问题。金朝初年已经形成基于武力的制度化政治... 关于金朝太祖、太宗时期政治、社会制度是国家形态,还是前国家形态——酋邦(军事部落联盟、部族制),学界有两种截然不同看法。学界相关研究中使用最为频繁的史料存在着解读失误和运用不当的问题。金朝初年已经形成基于武力的制度化政治结构的形式和基于地缘关系的社会凝聚机制,具备国家的基本要素。女真人建立的金朝,在太祖、太宗时期已经是一个多民族国家,不是单纯的女真人酋邦(或部族体制),也不是包含了多民族的酋邦(或部族体制、或部落联盟)。 展开更多
关键词 国家 酋邦 女真旧俗 国论勃极制度 汉地枢密院
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Application of crystal plasticity modeling in equal channel angular extrusion 被引量:4
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作者 李赛毅 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第1期170-179,共10页
Some applications of crystal plasticity modeling in equal channel angular extrusion(ECAE) of face-centered cubic metals were highlighted.The results show that such simulations can elucidate the dependency of grain r... Some applications of crystal plasticity modeling in equal channel angular extrusion(ECAE) of face-centered cubic metals were highlighted.The results show that such simulations can elucidate the dependency of grain refinement efficiency on processing route and the directionality of substructure development,which cannot be explained by theories that consider only the macroscopic deformation behavior.They can also capture satisfactorily the orientation stability and texture evolution under various processing conditions.It is demonstrated that crystal plasticity models are useful tools in exploring the crystallographic nature of grain deformation and associated behavior that are overlooked or sometimes erroneously interpreted by existing phenomenological theories. 展开更多
关键词 severe plastic deformation equal channel angular extrusion TEXTURE crystal plasticity strain path grain refinement
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Microstructure and texture evolution in titanium subjected to friction roll surface processing and subsequent annealing 被引量:1
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作者 施梅勤 高山善匡 +2 位作者 马淳安 渡部英男 井上博史 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第11期2616-2627,共12页
Commercial purity and high purity titanium sheets were initially strained by a new technique, named as friction roll surface processing (FRSP). Severe strain was imposed into the surface layer and strain gradient wa... Commercial purity and high purity titanium sheets were initially strained by a new technique, named as friction roll surface processing (FRSP). Severe strain was imposed into the surface layer and strain gradient was formed through the thickness of the sheet. The microstructure and texture in as-strained state were investigated by optical microscopy and X-ray diffraction technique On the surface of the sheets, ultra-fine grains were found to have a sharp texture with a preferred orientation strongly related to the FRSP direction. The evolution of microstructure and crystallographic texture of FRSPed samples during recrystallization were also studied by electron back-scattered diffraction (EBSD) technique after being annealed at selected temperatures and time. The results indicated that the preferred orientations resulting from FRSP and annealing in the surface layer were formed during rolling and its recrystallization textures were reduced by FRSP. In addition, the texture evolved stably without change in main components during the annealing. 展开更多
关键词 TITANIUM friction roll surface processing severe plastic deformation preferred orientation RECRYSTALLIZATION textureevolution ultra-fine grains
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Andrej Belyj's Novel-myth Perterburg
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作者 吴倩 《Sino-US English Teaching》 2007年第3期57-60,共4页
Andrej Belyj is the main representative of Russia symbolism. Symbolists pursue the text mystique with massive utilization of myth. But here myth has changed and obtained new myth characteristic, which is manifested in... Andrej Belyj is the main representative of Russia symbolism. Symbolists pursue the text mystique with massive utilization of myth. But here myth has changed and obtained new myth characteristic, which is manifested in Perterburg. 展开更多
关键词 Andrej Belyj Perterburg new mythology novel-myth
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ε-strongly Efficient Solutions for Vector Optimization with Set-valued Maps 被引量:9
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作者 WANG Qi-liu 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第1期104-109,共6页
In locally convex Hausdorff topological vector spaces,ε-strongly efficient solutions for vector optimization with set-valued maps are discussed.Firstly,ε-strongly efficient point of set is introduced.Secondly,under ... In locally convex Hausdorff topological vector spaces,ε-strongly efficient solutions for vector optimization with set-valued maps are discussed.Firstly,ε-strongly efficient point of set is introduced.Secondly,under the nearly cone-subconvexlike set-valued maps,the theorem of scalarization for vector optimization is obtained.Finally,optimality conditions of ε-strongly efficient solutions for vector optimization with generalized inequality constraints and equality constraints are obtained. 展开更多
关键词 vector optimization ε-strongly efficient point nearly cone-subconvexlike setvalued maps ε-strongly efficient solutions the theorem of scalarization optimality conditions
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Endurance exercise and gut microbiota:A review 被引量:21
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作者 Núria Mach Dolors Fuster-Botella 《Journal of Sport and Health Science》 SCIE 2017年第2期179-197,共19页
Background: The physiological and biochemical demands of intense exercise elicit both muscle-based and systemic responses. The main adaptations to endurance exercise include the correction of electrolyte imbalance, a ... Background: The physiological and biochemical demands of intense exercise elicit both muscle-based and systemic responses. The main adaptations to endurance exercise include the correction of electrolyte imbalance, a decrease in glycogen storage and the increase of oxidative stress, intestinal permeability, muscle damage, and systemic inflammatory response. Adaptations to exercise might be influenced by the gut microbiota, which plays an important role in the production, storage, and expenditure of energy obtained from the diet as well as in inflammation,redox reactions, and hydration status.Methods: A systematic and comprehensive search of electronic databases, including MEDLINE, Scopus, Clinical Trials.gov, Science Direct,Springer Link, and EMBASE was done. The search process was completed using the keywords: "endurance", "exercise", "immune response","microbiota", "nutrition", and "probiotics".Results: Reviewed literature supports the hypothesis that intestinal microbiota might be able to provide a measureable, effective marker of an athlete's immune function and that microbial composition analysis might also be sensitive enough to detect exercise-induced stress and metabolic disorders. The review also supports the hypothesis that modifying the microbiota through the use of probiotics could be an important therapeutic tool to improve athletes' overall general health, performance, and energy availability while controlling inflammation and redox levels.Conclusion: The present review provides a comprehensive overview of how gut microbiota may have a key role in controlling the oxidative stress and inflammatory responses as well as improving metabolism and energy expenditure during intense exercise. 展开更多
关键词 ENDURANCE EXERCISE Immune response MICROBIOTA NUTRITION PROBIOTICS
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Effects of non-isothermal annealing on microstructure and mechanical properties of severely deformed 2024 aluminum alloy 被引量:8
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作者 Saeed KHANI MOGHANAKI Mohsen KAZEMINEZHAD 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第1期1-9,共9页
Microstructure and mechanical properties of AA2024 after severe plastic deformation (SPD) and non-isothermal annealing were investigated. The non-isothermal treatment was carried out on the severely deformed AA2024,... Microstructure and mechanical properties of AA2024 after severe plastic deformation (SPD) and non-isothermal annealing were investigated. The non-isothermal treatment was carried out on the severely deformed AA2024, and the interaction between restoration and precipitation phenomena was investigated. Differential scanning calorimetry, hardness and shear punch tests illustrate that static recovery and dissolution of GPB zones/Cu-Mg co-clusters occur concurrently through non-isothermal annealing. Scanning electron microscope and electron backscatter diffraction illustrate that non-isothermal annealing of deformed AA2024 up to 250 ℃ promotes the particle-free regions and also particle stimulated nucleation. Results show that through heating with the rate of 10 ℃/min up to 250 ℃, the ultimate shear strength and the hardness are maximum due to the presence of S'/S phases which have been detected during non-isothermal differential scanning calorimetry experiment. Also, recrystallization phenomenon occurs in temperature range which includes the dissolution of S'/S phases. The concurrent recrystallization and dissolution of S'/S phase at 380 ℃ have been verified by differential scanning calorimetry, mechanical properties, and optical microscope. 展开更多
关键词 AA2024 alloy severe plastic deformation non-isothermal annealing MICROSTRUCTURE mechanical properties
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Predicting landslide scenes under potential earthquake scenarios in the Xianshuihe fault zone, Southwest China 被引量:15
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作者 ZHANG Yong-shuang YANG Zhi-hua +3 位作者 GUO Chang-bao WANG Tao WANG Dong-hui DU Guo-liang 《Journal of Mountain Science》 SCIE CSCD 2017年第7期1262-1278,共17页
Earthquake-induced landslides can seriously aggravate the earthquake's destructive consequences and have caused widespread concern in recent decades. The Xianshuihe fault is a large active left-lateral strike-slip... Earthquake-induced landslides can seriously aggravate the earthquake's destructive consequences and have caused widespread concern in recent decades. The Xianshuihe fault is a large active left-lateral strike-slip fault in the southeast margin of Qinghai-Tibet Plateau, Southwest China, where the frequent strong earthquakes have brought abundant geo-hazards. This study focuses mainly on exploring and predicting the landslide scenes induced by the potential earthquakes. Firstly, the sophisticated Newmark model is improved through landslide cases induced by the Ms7.9 Luhuo earthquake in 1973 to adapt the field seismotectonics of the Xianshuihe fault zone. Then, it is used to predict the landslide scenes under one speculated potential earthquake scenario with the similar focal mechanism with the Luhuo earthquake. The preliminary results show that the slope displacement resulted from Newmark model can reflect spatial distribution characteristics ofearthquake-induced landslides. The predicted potential earthquake-induced landslide scenes present an obvious extending trend along the Xianshuihe fault. The landslide hazard is greater in the northeast regions than southwest regions of the Xianshuihe fault, where there are more complex topographic conditions. The study procedure will be a helpful demonstration for exploration and prediction of landslide scenes under potential earthquakes in the regions with high seismic activity. 展开更多
关键词 Qinghai-Tibet Plateau Xianshuihe fault Potential earthquake LANDSLIDE Newmark model
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Origin of the Volcanic Rocks Erupted in the Eastern Manus Basin:Basaltic Andesite-Andesite-Dacite Associations 被引量:3
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作者 MA Yao ZENG Zhigang +2 位作者 CHEN Shuai YIN Xuebo WANG Xiaoyuan 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第3期389-402,共14页
There has been much recent interest in the origin of intermediate lava and several hypotheses are: 1) direct melting of the mantle under water-saturated conditions, 2) partial melting of altered crust, 3) fractional c... There has been much recent interest in the origin of intermediate lava and several hypotheses are: 1) direct melting of the mantle under water-saturated conditions, 2) partial melting of altered crust, 3) fractional crystallization of parent magma, and 4) magma mixing of mafic magmas with dacitic/rhyolitic magmas. Volcanic rocks series ranging from basaltic andesite to dacite(SiO_2 ranges from 53.8 to 63.0 wt.%) from the eastern Manus Basin were detected for major and trace element compositions to understand their origin. Low H_2O contents, positive correlations of La-SiO_2 and Yb-SiO_2, oxygen isotope data and the indistinct change of trace element concentrations in oscillatory zoning of plagioclase phenocrysts rule out the models in which silicic lava results from direct melting of hydrous mantle, partial melting of altered oceanic crust or gabbros, and magma mixing, respectively. Besides, the geochemical data of whole rock and melt inclusions indicate that fractional crystallization plays a dominant role in generating the intermediate lava with subduction features. 展开更多
关键词 Eastern Manus Basin fractional crystallization volcanic rocks
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Clinical Evaluation of Color Doppler Ultrasound in Selecting the Optimal Treatment Modality for Infantile Hemangioma 被引量:6
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作者 MinLi JuanLiu +2 位作者 ValeskaMaya DanLuo Bingrong Zhou 《Chinese Medical Sciences Journal》 CAS CSCD 2017年第2期100-106,共7页
Objective We investigated the efficacy and safety of 1064 nm Nd: YAG laser, intense pulsed light (IPL), and lauromacrogol injection in the treatment of hemangioma, in order to evaluate the value of color Doppler u... Objective We investigated the efficacy and safety of 1064 nm Nd: YAG laser, intense pulsed light (IPL), and lauromacrogol injection in the treatment of hemangioma, in order to evaluate the value of color Doppler ultrasound guidance in choosing the optimal treatment modality. Methods Infantile patients who were clinical diagnosed as hemangiomas were randomly divided into group A, who had color Doppler ultrasound examinations before the treatment, and group B who had the treatment without ultrasound evaluation. Patients in the group A were assigned into subgroups according to the depth of lesion by sonography: group A-1 for those who had a lesion depth 〈1.2 mm, and took intense pulsed light therapy; group A-2 for those who had a lesion depth ≥1.2mm and 〈 3 mm, and took long pulse 1064 nm Nd:YAG laser therapy; group A-3 for those who had a lesion depth ≥3mm and 〈5 mm, and were treated by IPL combined with long pulse 1064 nm Nd:YAG laser treatment; Group A-4 for those who had a lesion depth ≥5 mm, and took lauromacrogol injection therapy. Patients in the group B took long pulse 1064 nm Nd:YAG laser treatment without preoperative ultrasound evaluation. The efficacy and adverse reactions of the treatments between the groups were evaluated and compared statistically. Results Totally 113 patients with 128 skin lesions were enrolled in this study, 85 in the group A (mean age 6.8±7.9 months) and 28 in the group B (mean age 6.9±9.9 months). The mean depth of hemangioma was 3.3±1.1 mm in the group A, ranging from 0.5-7.8 mm, with 0.8±0.4 mm, 2.2±0.4 mm, 4.2±0.6 mm and 6.2±0.7 mm in group A1, A2, A3 and A4, respectively. The cure rates and effective rates in the group A were significantly higher than those in the group B (cure rates: 64.5% vs 56.3%, U=3.378, P=0.045; effective rates: 89.5% vs 78.1%, U=4.163, P=0.041). The adverse effect rates of the group A (vesicle 20.0%, pigmentation 46.9%, scarring 17.7%) were lower than those of the group B (vesicle 21.9%, pigmentation 60.4%, scarring 25.0%). Incidences of pigmentation and scarring were statistically significantly different (U=3.884, P=0.034, and U=4.016, P=0.032 respectively) between the two groups. Conclusion With the guidance of color Doppler ultrasound, the efficacy and safety of long pulse 1064 nmNd:YAG laser, intense pulsed light, and lauromacrogol injection in the treatment of infantile hemangioma have better outcomes compared to laser treatment alone without preoperative ultrasound examination. 展开更多
关键词 color Doppler ultrasound infantile hemangioma Nd:YAG laser intense pulsed light LAUROMACROGOL
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《金史》“篡改开国史”辨 被引量:4
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作者 程尼娜 《史学集刊》 CSSCI 北大核心 2022年第1期4-19,共16页
《金史》记载的金朝开国史是信史。“都勃极烈”不是金建国后女真国主的称号,而是生女真进入高级酋邦阶段后大酋长的称号。阿骨打建国之初只求民族自立,并没有灭辽的宏图,宋人文献称阿骨打是接受了杨朴“图霸天下,谋为万乘之国”的建议... 《金史》记载的金朝开国史是信史。“都勃极烈”不是金建国后女真国主的称号,而是生女真进入高级酋邦阶段后大酋长的称号。阿骨打建国之初只求民族自立,并没有灭辽的宏图,宋人文献称阿骨打是接受了杨朴“图霸天下,谋为万乘之国”的建议,才称帝建国的说法,既不符合金建国前后女真人的政治生态,也不符合杨朴的身份,当是宋人的演绎。在金向辽请求册封过程中杨朴的事迹是真实的,《金史》对此并未隐匿。宋晁公迈《历代纪年》成书早于《太祖实录》,明确记载金初存在“收国”年号。《太祖实录》没有虚构和编造金朝建国时间、国号、年号,据此撰写的《金史》没有篡改开国史。 展开更多
关键词 《金史》 开国史 都勃极 杨朴 “收国”
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Brain-derived neurotrophic factor(BDNF) as a potential mechanism of the effects of acute exercise on cognitive performance 被引量:6
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作者 Aaron T.Piepmeier Jennifer L.Etnier 《Journal of Sport and Health Science》 SCIE 2015年第1期14-23,共10页
The literature shows that improvements in cognitive performance may be observed following an acute bout of exercise. However, evidence in support of the biological mechanisms of this effect is still limited. Findings ... The literature shows that improvements in cognitive performance may be observed following an acute bout of exercise. However, evidence in support of the biological mechanisms of this effect is still limited. Findings from both rodent and human studies suggest brain-derived neu- rotrophic factor (BDNF) as a potential mechanism of the effect of acute exercise on memory. The molecular properties of BDNF allow this protein to be assessed in the periphery (pBDNF) (i.e., blood serum, blood plasma), making measurements of acute exercise-induced changes in BDNF concentration relatively accessible. Studies exploring the acute exercise--pBDNF--cognitive performance relationship have had mixed findings, but this may be more reflective of methodological differences between studies than it is a statement about the role of BDNE For example, significant associations have been observed between acute exercise-induced changes in pBDNF concentration and cognitive performance in studies assessing memory, and non-significant associations have been found in studies assessing non-memory cognitive domains. Three suggestions are made for future research aimed at understanding the role of BDNF as a biological mechanism of this relationship: 1) Assessments of cognitive performance may benefit from a focus on various types of memory (e.g., relational, spatial, long-term); 2) More finegrained measurements of pBDNF will allow for the assessment of concentrations of specific isoforms of the BDNF protein (i.e., immature, mature); 3) Statistical techniques designed to test the mediating role of pBDNF in the acute exercise-cognitive performance relationship should be utilized in order to make causal inferences. 展开更多
关键词 ISOFORMS MEDIATORS MEMORY Mental health Physical activity
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Evolution of microstructure, phase composition, and tensile properties of severely cold deformed titanium metastable β alloy in rapid continuous heating 被引量:3
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作者 P.E.MARKOVSKY V.I.BONDARCHUK +1 位作者 YU.V.MATVIYCHUK O.P.KARASEVSKA 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第5期1365-1371,共7页
Influence of severe cold deformation of titanium alloy Ti-1.5%A1-6.8%Mo-4.5%Fe in metastable β condition on the evolution of phase composition, microstructure, and tensile properties during continuous rapid heating w... Influence of severe cold deformation of titanium alloy Ti-1.5%A1-6.8%Mo-4.5%Fe in metastable β condition on the evolution of phase composition, microstructure, and tensile properties during continuous rapid heating was studied. As-deformed alloy was characterized by quasi-amorphous single-phase β condition with an abnormal temperature dependence of electric resistance that was normalized after 48 h exposure at room temperature as a result of isothermal ω phase precipitation. Subsequent rapid heating with a rate of 5 ℃/s caused recovery and recrystallization. Tensile properties of the alloy after different treatments were determined and discussed. 展开更多
关键词 titanium alloy severe cold deformation rapid heating recovery and recrystallization phase composition MICROSTRUCTURE mechanical properties
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Severe plastic deformation of commercially pure aluminum using novel equal channel angular expansion extrusion with spherical cavity 被引量:3
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作者 Xiao-xi WANG Xiang ZHANG +2 位作者 Xin-yu JING Jun-chi YUAN Wei SONG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第10期2613-2624,共12页
Equal channel angular expansion extrusion with spherical cavity(ECAEE-SC)was introduced as a novel severe plastic deformation(SPD)technique,which is capable of imposing large plastic strain and intrinsic back-pressure... Equal channel angular expansion extrusion with spherical cavity(ECAEE-SC)was introduced as a novel severe plastic deformation(SPD)technique,which is capable of imposing large plastic strain and intrinsic back-pressure on the processed billet.The plastic deformation behaviors of commercially pure aluminum during ECAEE-SC process were investigated using finite element analysis DEFORM-3D simulation software.The material flow,the load history,the distribution of effective strain and mean stress in the billet were analyzed in comparison with conventional equal channel angular extrusion(ECAE)process.In addition,single-pass ECAEE-SC was experimentally conducted on commercially pure aluminum at room temperature for validation,and the evolution of microstructure and microhardness of as-processed material was discussed.It was shown that during the process,the material is in the ideal hydrostatic stress state and the load requirement for ECAEE-SC is much more than that for ECAE.After a single-pass ECAEE-SC,an average strain of 3.51 was accumulated in the billet with homogeneous distribution.Moreover,the microstructure was significantly refined and composed of equiaxed ultrafine grains with sub-micron size.Considerable improvement in the average microhardness of aluminum was also found,which was homogenized and increased from HV 36.61 to HV 70.20,denoting 91.75%improvement compared with that of the as-cast billet. 展开更多
关键词 severe plastic deformation equal channel angular expansion extrusion with spherical cavity(ECAEE-SC) numerical simulation strain accumulation grain refinement
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Cannabinoid hyperemesis syndrome:Clinical diagnosis of an underrecognised manifestation of chronic cannabis abuse 被引量:2
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作者 Siva P Sontineni Sanjay Chaudhary +1 位作者 Vijaya Sontineni Stephen J Lanspa 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第10期1264-1266,共3页
Cannabis is a common drug of abuse that is associated with various long-term and short-term adverse effects. The nature of its association with vomiting after chronic abuse is obscure and is underrecognised by clinici... Cannabis is a common drug of abuse that is associated with various long-term and short-term adverse effects. The nature of its association with vomiting after chronic abuse is obscure and is underrecognised by clinicians.In some patients this vomiting can take on a pattern similar to cyclic vomiting syndrome with a peculiar compulsive hot bathing pattern,which relieves intense feelings of nausea and accompanying symptoms.In this case report,we describe a twenty-two year-old-male with a history of chronic cannabis abuse presenting with recurrent vomiting,intense nausea and abdominal pain.In addition,the patient reported that the hot baths improved his symptoms during these episodes.Abstinence from cannabis led to resolution of the vomiting symptoms and abdominal pain.We conclude that in the setting of chronic cannabis abuse,patients presenting with chronic severe nausea and vomiting that can sometimes be accompanied by abdominal pain and compulsive hot bathing behaviour,in the absence of other obvious causes,a diagnosis of cannabinoid hyperemesis syndrome should be considered. 展开更多
关键词 CANNABINOID CANNABIS Cyclic vomiting HYPEREMESIS Marijuana VOMITING
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